Rotary pivoted hammer



April 8, 1930. J. P. I'=OLSTER 1,753,473

ROTARY PIVOTED HAMMER Filed March 14, 1928 I I l m I /.9 I it yn] 4 9 I? L i 1 A4 /7 F153. 2. 'f & I4 I I I /7 /2 A A; /7 ll? A INVENTOR ATTORNEY.

Patented Apr. 8, 1930 N D S ATES PATENT OFFICE JOHN 'P. POLSTER,

ROTARY PIVO'IED HAMMER .Application filed March 14, 1928. Serial No. 261,471.

' Thisinvention relates to certain new and useful improvements in rotary pivoted ham mers for. crushing pulverizers for coal and other suitable material, the peculiarities of which will be hereinafter fully described and claimed. i f The, mainobjects of my invention are: first, to provide a rot arypivoted hammer with openings through the bar head ofsuch shape as to allow the material being pulverized to pass outwardly from the'central space near the rotor shaft to 'theannular clearance space between the hammer circle and the. arcuate grinding surface where the pulverization is effected; secondly, to assist this. outward movementby guiding the material into said openings; thirdly, to macerate or pulverize the material as it seeks said openings under centrifugal force; and fourthly, to further pulverize the material as it flows outward in streams from said openings. i

Inthe usual form of solidcross "bar head, the material being ground finds lodgment on the inner face of the head, and centrifugal force tends to cause it to maintain such position analogous to a bucket of water be-.

ing swung in acircular path,-the water re mains in the bucket due to centrifugal force. Should a hole be provided in the bottom of the bucket, the water will pass outward through it with velocity corresponding to thedegree of said force due to rotative speed. In the same manner, and for the same purpose, I provide suitable openings in said'cross bar head to permit the flow of the rotating material through the head from the inner to the outer face for further pulverizing action. Ac tual use of this hammer on coal has demon- 40 strated that it affords largely increased ca pacity over the usual form of solid bar head. In the accompanying drawing on which like reference numerals indicate correspond- .ing parts, v

Fig. 1 represents a crushing pulverizer of the arrow."

with one form of my improvedhammer mounted therein;

b Fig. 2, a detail front view of such a ham- Fig. 3, a similar view of the outer face of the same; Y

Fig. 4, a cross section on the line44 of Fig.2;

stirrup hammers illustrating my invention.

The sand casing is preferably closed except for. an opening at the top adapted for receivingthe feedvmaterial at one side 6 adjacent to a preliminary'breaker plate 7, and the discharge of the pulverized material at the other side 8 or elsewhere, after it has been pulverized between an arcuate grinding plate 9 (smooth or otherwise) and the outer face of said hammers as they rotate in the direction These hammers have the usual end shanks 10, spaced apart and'provided with holes 11 OI -ALTON, ILLINOIS, ASSIGNOR T0 ILLINOIS STOKER COMPANY, 01" P ALTON, ILLINOIS, A CORPORATION OF ILLINOIS attheir inner ends for said rods, and connected at their outer ends by across bar head provided with one or more longitudinal or other form of openings 12 and 13 for example, thus dividing the head into multiple bars 14, 15 and 16, that provide cutting edges 17 at their outer edges substantially 1n the outer circumferential cylindrical plane'of the heads to cooperate with said grinding surface 9 and breaker plate 7. These bars are preferably of increasing radial width inward from the outer face-the shorter bar preferably in front as indicated by the arrow, but having its outer cutting edge in the same cylindrical plane and circumferentially in front of the adjacent cutting edges, so as to facilitate the passage outward through said openings of the partly crushed material carried around by the rotating hammers, and thus subject to centrifugal force causing it to stream outward through said openings towards the arcuate' grinding surface. These cutting edges 17 are positioned substantially equally distant from said grinding plate 9 when operating, and each being fed independently by material passing outward through the substantially radial passage in front of it, operates practically simultaneously on their respective streams of material. Theinner edges l8 of saidbars are preferably beveled sharply an-'- gular to form cuttingiedg'es,and a plurality of inwardly extending, spaced, tooth like, an-

gular projections 19 having sharp front and side edges and located on the widest bar, tend to break up further the material impinging thereon as it seeks the said openings. These openings are substantially radial-as shown in all the figures. They have sides parallel as shown in Figs. 4 and 5, and diverg- 1 ing outward in Fig. 6 to facilitate thepas- My form of bar head is preferably mounted on two shanksas shown, but may be otherwise. supported without departing from'the spirit of my invention. v

.1. A stirrup hammer comprising a bar head provided with a longitudinal opening, substantially radial, forming" multiple bars, and a longitudinal web inclined rearwardly outward and extending slantingly toward the front forming ascoop adapted to deflect material outward through said opening. 7

2. A stirrup hammer comprising a bar headprovided with a longitudinal: opening, substantiallyradial, formingbars, anda longitudinal web inclined from its inner front edge rearwardly outward and integral with the rear bar forming ascoop adapted to dimet the material outwardly through said opening, substantially as and for the purpose described. 1 V

3. A, stirrup hammer comprising end shanks spaced apart and adapted for pivotal mounting at their inner ends and connected at their outer ends by a bar head,said head having multiple longitudinal openings, substantially radial and forming multiple bars of different radial width provided with cutting edges on their outer faces and angular sharply beveled cutting edges on their'inner faces,said openings diverging outwardly to form larger spaces at said outer faces and adapted for passage of material outward under centrifugal force, substantially as described.

4. A stirrup hammer comprising end shanks spaced apart and adapted for pivotal mounting at their inner ends and connected at their outer ends by a bar head,said head having multiple longitudinal openings substantially radial and forming multiple bars of di fferentradial width having cutting edges on both their outer and inner faces,-said openings diverging outwardly from the inner faceof said head,--and deflecting meanscarried by said ham-mer adapted to guide material from the front outwardly into said openings, substantially as described.

t 5. In combination with a rotary crushing pulverizer comprising an enclosed casing having an arcuate grinding surface and an opening for inlet of feed material and outlet of pulverized product, of a settof stirrup hammers each havingmultiple outer cutting edges all normallyin the cylindrical plane ofthe hammer circle and all operative simultaneously,- said hammers being mounted in said casing-and. adapted to cooperate with said grinding surface and each comprising end shanks: adapted" for pivotal mounting, and a bar head connectingasaid shanks and having substantially radial outwardly divergingpassages affording larger space in ontvof ad jacent simultaneously operative outer edges and adapted to deliver streams of material to the grinding cage. V

. 6. In combination with a crusher casing having anarcuate grinding surface, of rotary pivoted hammers, each having a bar head with substantially radial openings therethrough diverging outwardly, thereby facilitating outward fiow' ofv material and forming operative edges normally positioned substantiallyv an uniform distance from said grinding surface when operating and in sub stantially simultaneous action on the respec- 'tive streams of material flowing outwardly through. such openings, substantially as described, a

7. The; combination with a cylindrical grinding surface and a rotary shaft, of multiple pivotal hammers eccentrically mounted on said shaft and having heads with openings diverging outwardly to the outer face and forming cutting edges in said outer face circumferentially positioned and operative substantially in the cylindrical plane of rotation about theaxis of said shaft and adapt ed to'be fed with material'through said openings, substantially as described.

8. The combination with a casing having a cylindrical grinding surface, a rotary shaft mounted thereon, and rotary pivoted hammers operatively mounted eccentrically to said shaft with" their heads in; proximity to said grinding surface,said heads extending longitudinally and each composed of multiple cutting bars spaced apart andhaving outer cutting edges arranged parallel to each other and operative substantially in the circumferential cylindrical plane of rotation about the axis of said shaft while the spaces between said bars afi'ord outward passage of material in parallel streams adapted to be simultaneously reduced between said outer cutting edges and said cylindrical grinding surface, substantially as described.

In testimony whereof I have aifixed my signature.

JOHN P. POLSTER. 

